Southern Green Bean Casserole

This Southern Green Bean Casserole is creamy, savory, and topped with the perfect crispy finish.

It’s an old-school comfort food dish that brings everyone back to the table. This version uses fresh ingredients with all the traditional flavors we know and love.

Whether it’s for Sunday dinner, the holidays, or just because—it’s always the right time for this dish.

this recipe!

Why I Love This Recipe

This is one of those dishes I grew up with at every big meal. It was always warm, always creamy, and always the first to disappear from the table. I remember standing at the counter as a kid, sneaking those crispy onions off the top before dinner started. Now, it’s something I bring to potlucks or make on a cozy Sunday.

• Perfect balance of creamy and crunchy
• Easy to prep ahead and bake later
• Uses real ingredients—no canned soup here!
• A crowd favorite at any gathering

Serves: 6
Cook Time: 45 minutes

What You’ll Need

• 1 lb fresh green beans, trimmed
• 1 tablespoon olive oil
• 1 medium onion, finely chopped
• 8 oz mushrooms, sliced
• 2 cloves garlic, minced
• 2 tablespoons butter
• 2 tablespoons all-purpose flour
• 1 cup whole milk
• ½ cup chicken broth
• ½ cup shredded sharp cheddar cheese
• 1 teaspoon salt
• ½ teaspoon black pepper
• 1 ½ cups crispy fried onions

Pro Tips

• Blanch the green beans until just tender—don’t overcook or they’ll get mushy when baked.
• Use sharp cheddar for better flavor; mild cheddar gets lost in the cream sauce.
• Stir the sauce constantly when adding milk to avoid clumps.
• Add half the crispy onions into the casserole for extra flavor, not just on top.
• If using frozen green beans, thaw and pat dry to avoid watery casserole.

Tools You’ll Need

• Large pot
• Large skillet
• Whisk
• Chef’s knife
• Cutting board
• Mixing spoon
• Round ceramic baking dish (9-inch)
• Measuring cups and spoons

Substitutions and Variations

• Use canned green beans if you’re in a rush—drain them well.
• Swap the cheddar with gruyère or Monterey Jack for a different twist.
• For a vegetarian version, use vegetable broth instead of chicken broth.
• Add a pinch of cayenne if you like a little heat.

Make Ahead Tips

• You can fully assemble the casserole (without topping) the day before.
• Store it covered in the fridge.
• Add the fried onions just before baking so they stay crispy.

Recipe and Instructions

Step 1: Blanch the Green Beans

Bring a large pot of salted water to a boil. Add 1 lb trimmed green beans and cook for 4-5 minutes until bright green and just tender. Drain and immediately rinse under cold water to stop the cooking.

Step 2: Sauté Onion, Mushrooms, and Garlic

In a large skillet, heat 1 tablespoon olive oil over medium heat. Add 1 medium finely chopped onion and cook for 2-3 minutes until softened. Add 8 oz sliced mushrooms and cook for another 5 minutes until browned. Stir in 2 cloves minced garlic and cook for 1 more minute.

Step 3: Make the Cream Sauce

Add 2 tablespoons butter to the skillet. Once melted, sprinkle in 2 tablespoons all-purpose flour and whisk constantly for 1-2 minutes. Slowly pour in 1 cup whole milk and ½ cup chicken broth while whisking to create a smooth sauce. Cook for 4-5 minutes until thickened. Stir in ½ teaspoon black pepper, 1 teaspoon salt, and ½ cup shredded sharp cheddar cheese until melted.

Step 4: Combine Everything

Turn off the heat. Add the blanched green beans and half of the crispy fried onions (¾ cup) into the skillet with the sauce. Gently stir until everything is well coated.

Step 5: Transfer to Baking Dish and Top

Spoon the mixture into a round white ceramic baking dish. Spread it out evenly and top with the remaining ¾ cup crispy fried onions.

Step 6: Bake

Bake in a preheated oven at 375°F for 20-25 minutes until bubbly and golden brown on top.

Leftovers and Storage

• Store leftovers in an airtight container in the fridge for up to 4 days.
• Reheat in the oven at 350°F until warmed through or in the microwave.
• If the onions lose their crunch, toss on a fresh sprinkle before reheating.

Why This Recipe Works (Quick Science)

The flour and butter mix (called a roux) thickens the sauce. As the milk and broth heat, the starches expand and create that creamy texture. Cheddar adds sharpness, and baking the casserole lets the sauce soak into the green beans while the fried onions stay crisp on top. Each layer of flavor builds on the next.

Common Mistakes

• Skipping the blanch step—this leaves your green beans too crunchy.
• Not cooking the flour long enough—it can taste raw.
• Adding onions too early—they’ll burn during baking.
• Using pre-shredded cheese—it won’t melt as smoothly.

What to Serve With

• Roasted turkey or chicken
• Mashed potatoes
• Cornbread
• Cranberry sauce
• Glazed carrots

FAQ

Can I use canned green beans?
Yes, just drain them well and skip the blanching step.

Can I freeze this casserole?
You can freeze it before baking, but fried onions may get soggy. Add those fresh after thawing.

Is there a dairy-free option?
Yes! Use plant-based butter, milk, and cheese.

Final Thoughts

Southern Green Bean Casserole is more than just a side—it’s a memory in a dish. That creamy, crunchy bite brings warmth to any table. Give it a try, and let me know how it went in the comments below!